Answer:
the fine transparent tubular sheath which envelops the fibres of skeletal muscles.
Answer:
Although you normally hear about trying to reduce or eliminate friction, it actually has some important uses.
Since friction is a resistance force that slows down or prevents motion, it is necessary in many applications where you might want to hold items or do things and prevent slipping or sliding. In those cases, there is an advantage of having friction.
Quite often uses of frction can be seen from how things would be without friction. Without friction, you would not be able to walk, drive a car, or hold objects. Pens and pencils would not work.
Explanation:
These hydrogen atoms can come together in nuclear processes called fusion, which is the process that powers the sun, and through fusion, heavier atoms such as carbon and nitrogen are produced. These in turn undergo fusion to make even heavier atoms, and it is such processes that created all the atoms in the earth.
The connection between them is Vitamin D.
Vitamin D can be obtained from food and supplements, or synthesized by our bodies when we receive UV radiation in our skin, which is our major source. However, this vitamin comes <span>inactivated</span> and the only way to activate it is through enzymatic conversion (hydroxylation) in the liver and later in the kidneys.
This vitamin is necessary in the intestines because allows calcium and phosphorus to be observed, leading to normal growth and development of bones and teeth. Without enough vit D, bones become fragile, causing osteoporosis.
Answer:
c
Explanation:
a and b are fossil fuels Wich are almost gone. and d seems unlikely
